Stamos had Spring Break Affair with 17-Year-Old, Says Lawyer

Receive the latest celebrity updates in your inbox

The woman accused of trying to extort hundreds of thousands of dollars from "ER" and "Full House" actor John Stamos had a spring break fling with him when she was just 17, an attorney said.

The woman, Allison Coss, now 24, and an associate named Scott Sippola are both on trial in Michigan, where they launched their alleged scheme to blackmail the 46-year-old actor for $680,000, claiming they had photos of him with strippers and cocaine. Defense lawyer Sarah Henderson alleged the affair during opening arguments in federal court.

Top Entertainment Photos

Stamos, who attended the trial's opening day, declined comment to The Associated Press but is expected to testify.

His attorney, William Sobel, issued a statement through publicist Matt Polk that said: "The allegations made today in the courtroom by the defendants during opening statements will not be proven because they are simply untrue."

Prosecutors contend the pictures don't exist, and FBI agents testified Monday they found no such photos while searching the defendants' house after their arrest.

Coss and Stamos met in Orlando, Fla., in 2004 — shortly after Stamos had separated from his wife, actress and supermodel Rebecca Romijn. The couple divorced the next year.

Sippola's defense is that there was nothing illegal about his plan to sell embarrassing photos to magazines if Stamos refused to buy them He claims the FBI lost or destroyed the photos.

Sippola's attorney offered the defense as a deadline for a plea bargain elapsed and the case headed for a July 12 trial.

Assistant U.S. Attorney Maarten Vermaat said Sippola was raising a "standard defense in blackmail cases."